Venetian blinds are, of course, very well-known and can include horizontal or vertical louvers that can be opened and closed to alter the amount of light transmitted by the blind. In such blinds, the individual louvers can be turned or tilted so that the louvers overlap with each other (or at least abut one another) to close the blind or they can be turned or tilted parallel to the direction of light transmission to transmit light, for example into a room.
EP2540951 discloses a Venetian blind (10) that has several slats connected at each end to a motor-driven tilt mechanism, which acts to independently twist the slats between open and closed states.
U.S. Pat. No. 2,766,820 A discloses a window shade made up of a series of loops arranged in parallel to each other and together covering a window. Each loop has a rear section located on the windows-side of the shade and extending the full height of the window and a front section located on the room-side of shade. When the shade is closed, the rear sections of all the loops lie in substantially the same plane and light cannot be transmitted through the shade. However, a central slat is provided that can spread the front and back sections of the loops apart from each other to allow light to be transmitted through the shade into a room.
U.S. Pat. No. 6,227,279B discloses a Venetian type blind having pivoting/tilting slats or louvers. The louvers are segmented into a central section and outer sections and the blind includes a mechanism for pivoting and tilting the end sections of each louver relative to the middle section to control the amount of light admitted into a room.
JP2008261195A discloses a blind having vertical louvers. The louvers can be rotated about a vertical axis about an adjustable angle. The blind can be contracted and folded for storage when it is not used.
U.S. Pat. No. 3,299,943 A discloses a vertical louver window blind having a number of louvers, each of which is supported by a carriage that can be driven along a track, thereby extending the blind across a window or withdrawing it into one side. The carriages may be mounted on the upper frame of window. Each carriage may rotate the vertical louvers to adjust the light transmission of the blind.
US 2009071611 discloses a Venetian window blind made up of slats which are rotatable about their longitudinal axes to provide an open or closed blind. Each blind slat can carry part of a logo so that when the slats are rotated to close the blind, the different parts combine visually to provide the complete logo.